Video: New insights into how babies talk

SEATTLE — It is one of the great wonders of humanity: A baby hears parents and others talking and learns to speak.

Now, with parents volunteering their infants, researchers at the University of Washington are learning just what happens in the babies' brain to make that miracle unfold.

A cap with electrodes on the baby's head painlessly records signals from the brain's nerve cells. It all happens in a sound-proof room, on mom's lap, with one of the researchers working to keep the child happy.

The scientists play sounds like "Ba" and "Da" — key components of language.

As the child recognizes them, the machines record the brain pattern

"This is a technological tour de force," says Dr. Patricia Kuhl, who heads the project. "If you take a newborn — a six-monther and a 12-monther — dramatic changes are happening in the brain."

First, trillions of new nerve connections form in the part of the brain called Wernicke's Area, which is responsible for speech recognition. A few months later, neurons come alive in Broca's Area, the part responsible for speech.

"It's as though Broca's Area is saying, 'Oh, I recognize that. It's something that my mouth, and tongue, and lips can produce,'" says Kuhl.

The research has revealed that there can be enormous variation in how quickly the young brains respond. Researchers hope that by discovering how babies normally acquire language, they'll learn how to intervene if something is wrong and the process is not going properly

This could lead to better interventions to prevent autism, dyslexia and other problems.

But already it has reinforced what every parent knows — that the more you talk and read to your child — the faster the brain develops language.